1. Field of the Invention
The present invention relates generally to moving magnetic storage devices and their recording elements and more particularly to transducer-suspension structures which are suitable for batch fabrication and a method for making the structures.
2. Description of the Related Art
Moving magnetic storage devices, especially magnetic disk drives, are the memory device of choice. This is due to their expanded non-volatile memory storage capability together with a relatively low cost. Accurate retrieval of the stored memory from these devices becomes critical, requiring the magnetic transducer to be positioned as close to the media as possible. Optimally, the transducer should actually touch the media.
Disk files are information storage devices which utilize at least one rotatable magnetic media disk with concentric data tracks containing data information, a read/write transducer for reading the data from or writing the data to the various tracks, a slider for holding the transducer adjacent to the track generally in a flying mode above the media, a suspension for resiliently holding the slider and the transducer over the data tracks, and a positioning actuator connected to the transducer/suspension combination for moving the transducer across the media to the desired data track and maintaining the transducer over the data track center line during a read or a write operation. The transducer is attached to the air bearing slider which supports the transducer above the track of the disk by a cushion of air that is generated by the rotating disk. Alternatively, the transducer may also operate in contact with the disk. The suspension provides desired slider loading and dimensional stability between the slider and the actuator arm. The suspension is required to maintain the transducer and the slider adjacent to the data surface of the disk with as low a loading force as possible. The actuator positions the transducer over the correct track according to the data desired on a read operation or to the correct track for placement of the data during a write operation. The actuator is controlled to position the transducer over the correct track by shifting the combination generally transverse to the direction along the track.
In conventional disk drives, the transducer and the slider are formed separately from the suspension and then attached through a manual, operator controlled precision operation. Typically, these components are small and the positioning of each relative to the other must be exact. During operation, the transducer must be exactly positioned relative to the data track, which in turn means that the suspension must be exactly positioned onto the slider. The suspension must provide flexibility to pitch and roll motion for the slider relative to the direction of motion of the rotating disk and yet also provide resistance to yaw motion. Any error in the placement of the suspension relative to the slider may result in the destruction of both components. Even if the suspension and the slider are correctly positioned, electrical conductor leads to the transducer must then be connected to the transducer. The conductor leads are directed along the suspension and connected to an amplifier placed on the suspension or on the actuator. The conductor leads must not add to the spring stiffness of the slider while providing good electrical interconnection. The conductor leads are generally bonded by soldering or ultrasonic bonding, for example, to both the transducer output terminals and the amplifier by an operator. Again, errors can cause destruction of the entire combination. Touching the media presents unique problems in wear and, during operation of the disk file, the possibility of creating a "crash" of the media. To reduce the wear problem and "crash" potential, it has been recognized that the mass of the suspension system must be reduced to a minimum. Minimal mass optimizes any physical "impact" the head has upon the media and thereby reduces the possibility of damage and wear.
To this end there have been disclosed a variety of mechanisms which utilize a "reed" approach to producing the transducer-slider-suspension. Structured to work in a perpendicular recording environment, these devices permit the head and suspension to be easily manufactured laving: (i) precise throat height control, (ii) precise formation of air bearings to achieve specified flying heights, (iii) bonding of sliders to suspensions, and, (iv) easy routing of conductor leads.
U.S. Pat. Nos. 5,041,932; 5,073,242; and 5,111,351 entitled "Integrated Magnetic Read/Write Head/Flexure/Conductor Structure" granted to Harold J. Hamilton disclose an integral magnetic transducer/suspension/conductive structure having the form of an elongate dielectric flexure or suspension body with a magnetic read/write transducer embedded within at one end thereof. In a preferred embodiment, Hamilton discloses an elongate, dielectric flexure body of aluminum oxide having a magnetic pole structure and helical coil integrally formed at one end of the flexure body with embedded copper conductor leads running the length of the flexure body to provide electrical connection for the transducer. The integral structure is fabricated utilizing conventional vapor deposition and photolithography techniques. The integral transducer/suspension structure disclosed by Hamilton may be used in a contact recording system or in a system where the transducer flies above the storage medium on a cushion of air.
As noted earlier, contact recording permits higher signals and greater resolution unregulated by variations in flying height. Unfortunately, the wear associated with contact recording is usually not acceptable. Still another disadvantage is the requirement, in a perpendicular head, of two perpendicular planes which create processing problems. All of this has made the prior art perpendicular recording head unsuitable for high density recording.